Hi Lugia,
Oh wow, that's a serious beauty that Soundcraft Five series. With 54 frames you mean 54 faders? That's a beast of a machine! :-)
I just had a quick look here in Germany on eBay so far couldn't find much that's affordable, I found two serious large studio racks, used at about 18k Euro... not the prices you are talking about. Looks like there is a different market between the USA and Europe. Will check out further this week into this though.
Hold on... 400 lbs that's I guess getting close to 200 kilograms! That's a serious thing, did you hire a crane to first remove the roof of your house and then let the desk go down into your house or how did you manage to transport such a beast? I live in that kind of cheap build new houses where everything is built just at minimum specs to keep the house standing but that's it, I think if I would put somewhere a 200 kg mixer I think it goes through my ceilings ending up flatting my coffee table in the living room! ;-)
That Five mixer is just fantastic to look at, so I can imagine, or exactly I don't think I really can imagine, how fantastic that must be in usage, lovely! :-) Well done deal for S$ 1500! Have fun with it and I hope your floor can hold the weight ;-) Kind regards, Garfield.
For review reports of Eurorack modules, please refer to https://garfieldmodular.net/ for PDF formatted downloads